Methods for carrying out a sound test for detecting and/or analyzing material faults and/or mounting faults of components are already known. In order to evaluate deviations of a turbine blade with respect to the delivery state or design state, for example with respect to the tensioning of the blades, loosening of the attachment of the blades or the presence of fractures etc., for example the turbine blade is struck with a hammer when the turbine housing is open, and the resulting sound pattern is analyzed acoustically by trained and very experienced personnel without technical aids. This requires many years of experience in order to be able to differentiate “good” sound patterns from “bad” sound patterns. A problem when carrying out such a sound test is that when checking very inaccessibly arranged components said sound test involves a very large amount of expenditure since the components have to be made accessible for the implementation of the hammer blow. It is also problematic that the evaluation result has hitherto been of a subjective nature and therefore very susceptible to errors. Furthermore, for economic grounds it would be advantageous for such a sound test also to be able to be carried out by less experienced personnel.
In addition, endoscopes of the type mentioned at the beginning are known. They have been successfully used for many years in the field of technology for inspecting optically components which are difficult to access, without having to carry out costly disassembly operations. In particular rigid endoscopes and flexible endoscopes are contemporary types of endoscopes, wherein the so-called video endoscopes form a subgroup of the flexible endoscopes. All the endoscopes have in common the fact that they form a handling unit which, in the case of a rigid endoscope, is connected to a rigid shaft, and in the case of a flexible endoscope is connected to a shaft which is of flexible design. An image transmission device and a light transmission device are integrated into the shaft in such a way that image signals and light signals can be transmitted from the free end of the shaft to the handling unit. The image transmission device can be formed by a lens arrangement and an eyepiece which is arranged on the handling unit. Alternatively, as in the case of the video endoscope for the generation of images and transmission of images it is also possible to use digital technology with which video images can be displayed on a monitor which is either provided separately or attached to the handling unit. The image transmission device is nowadays implemented by a light guide fiber bundles which are arranged in the shaft and by which light which is emitted by a light source usually integrated into the handling unit is guided to the free end of the shaft.
Furthermore, the use of endoscopes is known with gripping tools and cutting tools in the medical field, for example for the removal of tissue samples or the like.
Taking this known art as a starting point, a purpose of the embodiments of the present invention is to make available an improved method of the type mentioned at the beginning with which sound tests for detecting and/or analyzing material faults and/or mounting faults can be carried out without difficulty and cost-effectively even on components which are difficult to access. In addition, a purpose of the embodiments of the present invention is to make available technical means for carrying out such a method.